diff --git a/src/battery.cpp b/src/battery.cpp
index 147e5d0b..454538a9 100644
--- a/src/battery.cpp
+++ b/src/battery.cpp
@@ -5,50 +5,48 @@
 // Local logging tag
 static const char TAG[] = "main";
 
-static void print_char_val_type(esp_adc_cal_value_t val_type) {
+esp_adc_cal_characteristics_t *adc_characs =
+    (esp_adc_cal_characteristics_t *)calloc(
+        1, sizeof(esp_adc_cal_characteristics_t));
+
+static const adc1_channel_t adc_channel = HAS_BATTERY_PROBE;
+static const adc_atten_t atten = ADC_ATTEN_DB_11;
+static const adc_unit_t unit = ADC_UNIT_1;
+
+void calibrate_voltage(void) {
+  // configure ADC
+  ESP_ERROR_CHECK(adc1_config_width(ADC_WIDTH_BIT_12));
+  ESP_ERROR_CHECK(adc1_config_channel_atten(adc_channel, atten));
+  // calibrate ADC
+  esp_adc_cal_value_t val_type = esp_adc_cal_characterize(
+      unit, atten, ADC_WIDTH_BIT_12, DEFAULT_VREF, adc_characs);
+  // show ADC characterization base
   if (val_type == ESP_ADC_CAL_VAL_EFUSE_TP) {
-    ESP_LOGD(TAG,
+    ESP_LOGI(TAG,
              "ADC characterization based on Two Point values stored in eFuse");
   } else if (val_type == ESP_ADC_CAL_VAL_EFUSE_VREF) {
-    ESP_LOGD(TAG,
+    ESP_LOGI(TAG,
              "ADC characterization based on reference voltage stored in eFuse");
   } else {
-    ESP_LOGD(TAG, "ADC characterization based on default reference voltage");
+    ESP_LOGI(TAG, "ADC characterization based on default reference voltage");
   }
 }
 
-uint16_t read_voltage(void) {
-  static const adc1_channel_t channel = HAS_BATTERY_PROBE;
-  static const adc_atten_t atten = ADC_ATTEN_DB_11;
-  static const adc_unit_t unit = ADC_UNIT_1;
-
-  // configure ADC1
-  ESP_ERROR_CHECK(adc1_config_width(ADC_WIDTH_BIT_12));
-  ESP_ERROR_CHECK(adc1_config_channel_atten(channel, atten));
-
-  // calibrate ADC1
-  esp_adc_cal_characteristics_t *adc_chars =
-      (esp_adc_cal_characteristics_t *)calloc(
-          1, sizeof(esp_adc_cal_characteristics_t));
-  esp_adc_cal_value_t val_type = esp_adc_cal_characterize(
-      unit, atten, ADC_WIDTH_BIT_12, DEFAULT_VREF, adc_chars);
-  print_char_val_type(val_type);
-
-  // multisample ADC1
+uint16_t read_voltage() {
+  // multisample ADC
   uint32_t adc_reading = 0;
   for (int i = 0; i < NO_OF_SAMPLES; i++) {
-    adc_reading += adc1_get_raw(channel);
+    adc_reading += adc1_get_raw(adc_channel);
   }
-
   adc_reading /= NO_OF_SAMPLES;
-
-  // Convert adc_reading to voltage in mV
+  // Convert ADC reading to voltage in mV
   uint16_t voltage =
-      (uint16_t)esp_adc_cal_raw_to_voltage(adc_reading, adc_chars);
+      (uint16_t)esp_adc_cal_raw_to_voltage(adc_reading, adc_characs);
 #ifdef BATT_FACTOR
   voltage *= BATT_FACTOR;
 #endif
-  ESP_LOGD(TAG, "Raw: %d / Voltage: %dmV", adc_reading, voltage);
+  ESP_LOGI(TAG, "Raw: %d / Voltage: %dmV", adc_reading, voltage);
   return voltage;
 }
+
 #endif // HAS_BATTERY_PROBE
\ No newline at end of file
diff --git a/src/battery.h b/src/battery.h
index d05dc9b1..93696fb5 100644
--- a/src/battery.h
+++ b/src/battery.h
@@ -5,8 +5,9 @@
 #include <esp_adc_cal.h>
 
 #define DEFAULT_VREF 1100 // tbd: use adc2_vref_to_gpio() for better estimate
-#define NO_OF_SAMPLES 64  // we do multisampling
+#define NO_OF_SAMPLES 64  // we do some multisampling to get better values
 
 uint16_t read_voltage(void);
+void calibrate_voltage(void);
 
 #endif
diff --git a/src/display.cpp b/src/display.cpp
index a5116041..52decae1 100644
--- a/src/display.cpp
+++ b/src/display.cpp
@@ -89,7 +89,7 @@ void init_display(const char *Productname, const char *Version) {
 
 } // init_display
 
-void refreshDisplay() {
+void refreshtheDisplay() {
 
   // set display on/off according to current device configuration
   if (DisplayState != cfg.screenon) {
@@ -109,13 +109,11 @@ void refreshDisplay() {
   u8x8.draw2x2String(0, 0,
                      buff); // display number on unique macs total Wifi + BLE
 
-/*
 // update Battery status (line 2)
 #ifdef HAS_BATTERY_PROBE
   u8x8.setCursor(0, 2);
-  u8x8.printf("B:%.1fV", read_voltage() / 1000.0);
+  u8x8.printf("B:%.1fV", batt_voltage / 1000.0);
 #endif
-*/
 
 // update GPS status (line 2)
 #ifdef HAS_GPS
diff --git a/src/display.h b/src/display.h
index a444de7b..c88d9315 100644
--- a/src/display.h
+++ b/src/display.h
@@ -6,7 +6,7 @@
 extern uint8_t DisplayState;
 
 void init_display(const char *Productname, const char *Version);
-void refreshDisplay(void);
+void refreshtheDisplay(void);
 void DisplayKey(const uint8_t *key, uint8_t len, bool lsb);
 
 #endif
\ No newline at end of file
diff --git a/src/globals.h b/src/globals.h
index b02bc37a..10324461 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -40,8 +40,8 @@ typedef struct {
 extern configData_t cfg;                      // current device configuration
 extern char display_line6[], display_line7[]; // screen buffers
 extern uint8_t channel;                       // wifi channel rotation counter
-extern uint16_t macs_total, macs_wifi, macs_ble; // display values
-extern std::set<uint16_t> macs;                  // temp storage for MACs
+extern uint16_t macs_total, macs_wifi, macs_ble, batt_voltage; // display values
+extern std::set<uint16_t> macs; // temp storage for MACs
 extern hw_timer_t *channelSwitch, *sendCycle;
 extern portMUX_TYPE timerMux;
 
diff --git a/src/main.cpp b/src/main.cpp
index 55ba10d2..784fe0ad 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -30,13 +30,16 @@ licenses. Refer to LICENSE.txt file in repository for more details.
 configData_t cfg; // struct holds current device configuration
 char display_line6[16], display_line7[16]; // display buffers
 uint8_t channel = 0;                       // channel rotation counter
-uint16_t macs_total = 0, macs_wifi = 0, macs_ble = 0; // globals for display
-hw_timer_t *channelSwitch = NULL, *displaytimer = NULL,
-           *sendCycle = NULL; // configure hardware timer for cyclic tasks
+uint16_t macs_total = 0, macs_wifi = 0, macs_ble = 0,
+         batt_voltage = 0; // globals for display
+
+// hardware timer for cyclic tasks
+hw_timer_t *channelSwitch = NULL, *displaytimer = NULL, *sendCycle = NULL,
+           *battCycle = NULL;
 
 // this variables will be changed in the ISR, and read in main loop
 static volatile int ButtonPressedIRQ = 0, ChannelTimerIRQ = 0,
-                    SendCycleTimerIRQ = 0, DisplayTimerIRQ = 0;
+                    SendCycleTimerIRQ = 0, DisplayTimerIRQ = 0, BattReadIRQ = 0;
 
 portMUX_TYPE timerMux =
     portMUX_INITIALIZER_UNLOCKED; // sync main loop and ISR when modifying IRQ
@@ -116,17 +119,30 @@ void IRAM_ATTR DisplayIRQ() {
   DisplayTimerIRQ++;
   portEXIT_CRITICAL_ISR(&timerMux);
 }
-
 void updateDisplay() {
-  // refresh display according to refresh cycle setting
   if (DisplayTimerIRQ) {
     portENTER_CRITICAL(&timerMux);
     DisplayTimerIRQ = 0;
     portEXIT_CRITICAL(&timerMux);
-    refreshDisplay();
+    refreshtheDisplay();
   }
 }
+#endif
 
+#ifdef HAS_BATTERY_PROBE
+void IRAM_ATTR BattCycleIRQ() {
+  portENTER_CRITICAL(&timerMux);
+  BattReadIRQ++;
+  portEXIT_CRITICAL(&timerMux);
+}
+void readBattery() {
+  if (BattReadIRQ) {
+    portENTER_CRITICAL(&timerMux);
+    BattReadIRQ = 0;
+    portEXIT_CRITICAL(&timerMux);
+    batt_voltage = read_voltage();
+  }
+}
 #endif
 
 #ifdef HAS_BUTTON
@@ -313,6 +329,13 @@ void setup() {
   strcat_P(features, " GPS");
 #endif
 
+// initialize battery status if present
+#ifdef HAS_BATTERY_PROBE
+  strcat_P(features, " BATT");
+  calibrate_voltage();
+  batt_voltage = read_voltage();
+#endif
+
 // initialize display if present
 #ifdef HAS_DISPLAY
   strcat_P(features, " OLED");
@@ -344,6 +367,14 @@ void setup() {
   timerAlarmWrite(sendCycle, cfg.sendcycle * 2 * 10000, true);
   timerAlarmEnable(sendCycle);
 
+  // setup battery read cycle trigger IRQ using esp32 hardware timer 3
+#ifdef HAS_BATTERY_PROBE
+  battCycle = timerBegin(3, 8000, true);
+  timerAttachInterrupt(battCycle, &BattCycleIRQ, true);
+  timerAlarmWrite(battCycle, BATTREADCYCLE * 10000, true);
+  timerAlarmEnable(battCycle);
+#endif
+
 // show payload encoder
 #if PAYLOAD_ENCODER == 1
   strcat_P(features, " PAYLOAD_PLAIN");
@@ -431,6 +462,10 @@ void loop() {
     readButton();
 #endif
 
+#ifdef HAS_BATTERY_PROBE
+    readBattery();
+#endif
+
 #ifdef HAS_DISPLAY
     updateDisplay();
 #endif
diff --git a/src/paxcounter.conf b/src/paxcounter.conf
index 14d76816..501cc1c2 100644
--- a/src/paxcounter.conf
+++ b/src/paxcounter.conf
@@ -58,11 +58,10 @@
 #define BUTTONPORT                      5       // Port on which device sends button pressed signal
 #define CAYENNEPORT                     2       // Port for Cayenne LPP 2.0 packet sensor encoding
 
-// Default RGB LED luminosity (in %)
-#define RGBLUMINOSITY                   30      // 30%
-
-// OLED Display refresh cycle (in Milliseconds)
-#define DISPLAYREFRESH_MS               40      // e.g. 40ms -> 1000/40 = 25 frames per second
+// Some hardware settings
+#define RGBLUMINOSITY                   30      // RGB LED luminosity [default = 30%]
+#define DISPLAYREFRESH_MS               40      // OLED refresh cycle in ms [default = 40] -> 1000/40 = 25 frames per second
+#define BATTREADCYCLE                   60      // battery measuring cycle in seconds [default = 60 secs]
 
 // LMIC settings
 // define hardware independent LMIC settings here, settings of standard library in /lmic/config.h will be ignored